This invention relates to ammunition, particularly to primers, and more particularly to the use of an inorganic reactive multilayer (RML) as the primary chemical initiator in order to control the usable life-time of cartridges and detonators for explosives.
Cartridge primers, are the initial explosive train component in ammunition consisting of a cartridge case, propellant, and projectile. Cartridge primers generally consist of a thin metal cup, a metal anvil, and an explosive protected by foil and sealed with lacquer. The explosive or primary initiator is a shock-sensitive material such as fulminate of mercury, potassium chlorate, or lead styphnate. Lead styphnate has been used as the primary initiator in primers for the past fifty years. These cartridge primers have a virtually unlimited shelf-life. It is not surprising that the performance and reliability of ammunition that has been stored properly for more than fifty years is indistinguishable from new ammunition. Hence, ammunition manufactured with primers using modern chemical initiators can be expected to remain functional indefinitely. This quality is essential to the stockpiling of ammunition required by the military. However, this quality also creates a potentially dangerous situation because it allows anyone to stockpile large quantities of ammunition without any anticipated legitimate use. Subversive individuals and groups are therefore able to “out-gun” law enforcement personnel attempting to execute lawful search and arrest warrants because of the nearly endless amount of ammunition that can be expended from a fortified position in an armed conflict.
Recently, there have been efforts to impose increasingly stricter gun-control measures by state and federal legislatures, as well as a call for “safer bullets” by the U.S. Surgeon General, in order to reduce the occurrence of violent crime. The effectiveness of new gun control legislation is the subject of much debate due to loop-holes in the laws and, perhaps, more importantly, the number of firearms already owned by the general public (estimated to be as high as 200 million firearms nationwide). There is a need for alternate methods of reducing the occurrence of gun related violence, such as controlling the availability of ammunition. One method of controlling the availability of ammunition that has been suggested is to limit its usable service-life. It is generally accepted that limiting the shelf-life of the primer is the most efficient method of controlling the usable service life of ammunition, because the complexity of the primer makes it the most difficult cartridge component to duplicate or replace.
While prior efforts have been contemplated to reduce the long shelf-life problem, no solution has yet been found. For example, one of the largest suppliers of primers to the ammunition reloader, CCI, has stated, “On the shelf life issue, our chemists have decades of experience in designing chemical initiators, and they know of no way to ‘kill’ a primer after two years that won't kill it tomorrow. The chemical technology to limit shelf life simply does not exist. Primer shelf life is measured in decades (see Shooting Times/September 1994, “Precision Reloading” by Rick Jamison, pp. 28-32 and 35).
The present invention fills the above-mentioned needs by providing a method of controlling the availability of ammunition by limiting the functional shelf-life of the primer to months or years, and thus offers an alternate and simple method of reducing the occurrence of firearms-related violence.